1. Field of the Invention
The present invention relates to an active matrix type display device using a light emitting element in a pixel, and an electronic device incorporating such a display device.
2. Description of the Related Art
Development of flat-panel emissive display devices using an organic EL (electro luminescence) device as a light emitting element has recently been actively underway. The organic EL device uses a phenomenon in which an organic thin film emits light when an electric field is applied to the organic thin film. The organic EL device is driven with an applied voltage of 10 V or lower, and thus consumes low power. In addition, the organic EL device is a self-luminous element that emits light by itself. Therefore a need for an illuminating member is eliminated, and it is thus easy to achieve a reduction in weight and a reduction in thickness. Further, the organic EL device has a very high response speed of a few us, so that no afterimage occurs at a time of displaying a moving image.
Of flat-panel emissive display devices using an organic EL device in a pixel, active matrix type display devices having a thin film transistor formed as a driving element in each pixel in an integrated manner, in particular, are being actively developed. Active matrix type flat-panel emissive display devices are described in Japanese Patent Laid-Open Nos. 2003-255856, 2003-271095, 2004-133240, 2004-029791, 2004-093682 for example.